An electronic oscillator generally includes a resonant circuit that produces a periodic, time-varying electrical signal of a given frequency—the inverse of the resonant circuit's period determines its frequency. The electrical signal may be used, for instance, to keep track of the passage of time by counting a number of signal oscillations. A common electronic oscillator employs a quartz crystal as its resonating element, although other types of piezoelectric materials (e.g., polycrystalline ceramics) may also be used.
Electronic oscillators have been used to generate clock signals for lots of electronic devices. Electronic oscillators are an important component of radio frequency (RF) and electronic devices. Today, product design engineers often do not find themselves designing oscillators because the oscillator circuitry is provided on the device. However, most current electronic oscillators have issues because of the analog AGC loop used with the electronic oscillators. For example, the analog AGC may cause instability in the AGC loop and/or improper starting of the oscillator when initial seed current is applied.